Cooling unit for refrigerating systems



E. H. STEEDMAN COOLING UNIT FOR REFRIGERATING SYSTEMS Aug. 11,1931.

Filed Feb. e, 192e LANE,

UNITED STA Patented Aug.Y 11, 1931 EDWINH. STEEDMAN, OF ST. LOUIS,MISSOURI COOLING UNIT FOR REFRIGERATING- SYSTEMS Application AtiledFebruary 6, .1928. Serial No. 252,299.

15 Figure of the drawings is a This invention relates to cooling unitsfor l refrigerating systems of small capacity, such as are used indomestic refrigerators, ice cream cabinets and similar apparatus. vThemain' objectbf my invention is to provide an eiiicient cooling unit ofinexpensive construction and attractive .appearance, which is equipped'with a cold plate that forms a very eiiicient heat absorption '20 away,of the cooling unit shown in Figure 1.

Figure 3 is a vertical longitudinal sec- -vtional viewV of the coolingunit shown. in vFigure 1; and l Y igure 4 is-a transverse sectionalview,

z5 illustrating another form of my invention,

wherein the cold plate of the unit is formed from an element-.separateand distinct from the hollow side walls of the unit and attachedto saidwalls. A

30 Referring to Figures 1, 2 and 3, which illustrateone form of myinvention, A and B designate two shells or members arranged one withinthe other and provided with coeperatngrportions that arel adapted to be.p86 combined in such a 'way as to form' a double l wall shell'thatcontains a refrigerating mediumand which surroundsa space at the I'center of the cooling unit that is adapted to receive materialorart'icles which it is desired to'cool', 'chill or freeze, said membersvA and B being preferably formed vfrom sheet metal. inner member' Av isprovided with twofvertically-disposed side" walls 1, 'a top walll2-integrall5'f connected' tol said side walls, and `a flat orsubstantially flat"botto'm wall 3 integrally connected to .said sidewalls. The outer member A'B is of similar4 form and is provided withsidev walls4 1?,a top wall 2! anda bottom wall 3" similar construction,or the topand bottom produced by a welding, brazing inforce andstrengthenthe opposed portions lof the members A and B so as to preventall integrally connected together. The marginal edges of the kside wallportions and of the bottom wall portions of said members A and B areconnected together by gas-tight joints ltpreferably produced by abrazing, welding, soldering or similar seaming operation. The opposedtop wall portions2 and 2a' of the members A s o shaped that they willform t e bottom and top wall, respectively, of an integral float chamber5 for the iioat 6 that controls the valve which governs the admission ofythe refrigerating medium to the passageway formed by the opposedportions of the members A and B. It is immaterial how the top and bottomwalls of the oat chamber are joined together. In the embodiment of myinvention herein shown, the float chamber 5 is provided with a frontwall 7 formed preferably by a plate, casting or other element that isconnected by gas-tight joints with the front edges of the top wallportions of the members A and B. Said float chamber can be providedwithA a rearwall' of walls of said chamber can be'bent inwardly towardseach other, as shown in Fi re 3, and joined togetherv by a gas-tightJoint 8l or other suitable seaming operation.. vIn order to re- 80distortion, due to internalpressure, some of the 'opposed portions ofsaid members can be connected together at numerous points 9 within theirmarginal-,ed by spotweld-` ing,or inany other suita le way, and`1f 1t isdesired to.i increase the surface of the unit that is exposed to the.airy in the refrigerator .or other structure in which the 9 unitis'used, fins 10 can be attached to the. exteriorof the unit, asindicated in brokenlines in4 Figure 2.- .Owing to the fact that the `Lrefrigeratingmedium is in eicient thermal conductivity with the bottomwall B of the 'space a: of the unit, this portion lof' the um'tconstitutes a cold plate that forms avery .eiicient heat absorption`means for rapidly abstracting heat from an icecreammixture or othersubstance in e, .container that 1s and Bare referablyV l arrangedin anupright position on the bottom wall 3. The portion 3 of the cold platethat serves as a supporting surface for the the fact that the bottom ofthe container is maintained in good and adequate thermal conductivitywith the heat absorption means, and if relatively rapid freezing orcooling is desired, water can be spread over the bottom of the containeror over the portion, of the cold plate on which the container rests, soas to fill any voids or interstices between said opposed surfaces, andthus insure a good thermal connection between the container and the heatabsorption means. In order to facilitate the use of water or othersuitable material used to insure good f and adequate thermalconductivity between the container that holds the material being frozenor cooled and the heat .absorption means on which said container isositioned, the bottom portion 3 of the mem ler A that constitutes thetop surface of said heat absorption means is preferably providedadjacent its marginal edge with a rib 11, as shown in Figure 3, so as toform a pocket o r depression on the cold plate of the unit that iscapable` of holding a thin film of liquid. The inner faces of the sidewalls of the space of the unit are preferably provided withhorizontally-disposed supports 12 that are used to sustain pans or trays(not shown) which hold water or other material that it is desired tofreeze, chill or cool, said supports 12 being combined with said sidewalls in any suitable way.

If desired the unit can consist of an o en bottom structure equippedwith a cold p ate formed by a separate member of any desired form, as,for example, a hollow member 3l' of the-kind illustrated in Figure 4,which is connected by welding, brazing or any other suitable method tothe hollow side walls of the unit, said member 3b being provided withports or openings 3 that establish communication between the interior ofsame and the interior of the hollow side walls of the unit, so as topermit the refrigerating medium to circulate freely through said coldplate.

The float chamber 5 is provided with a hole of suicient size to permitthe float 6 to be introduced into said chamber, and said hole isnormally closed by a cover plate or closure 16 equipped with a gasket 17and held 1n position by fastening devices 1,8.

y Said hole can be located in any suitable portion of theoat chamber,but it is herein shown as bem formed in a plate 7 ythat constitutes thefro t wall of the float chamber.

The valve mechanism that governs the admission of the refrigeratingmedium to the unit is preferably combined with or carried by the closure16 and is herein illustrated as comprising a valve 19 which is combinedwith the float 6 in such a way that when the level of the refrigeratingmedium in the float chamber 5 drops, the float 6 will move in adirection to open the valve 19, and thus admit more refrigerating mediumto the float chamber. Thereafter, when the level of the refrigeratingmedium in the float chamber rises, the float 6 will move in a directionto close the valve 19. The gas from the evaporated refrigerating mediumis sucked off by the compressor (not shown) through a conduit thatcommunicates with a hole 2() in the closure 16. The valve structure alsopreferably comprises a shut-off valve (not shown) that can be used forcutting oli' the supply of the refrigerating medium to the controllingvalve 19, said cutoff| valve being accessible by removing the gas-tightplug 22, shown in Figure 1.

A refrigerating unit of the construction above described is inexpensiveto manufacture, as it is constructed from shaped members, preferablysheet metal members, which, after being assembled, are connected t0-gether by a simple seaming operation, so as to produce a gas-tight,double wall shell that surrounds a center space for receiving articlesor materials which it is desired to cool, freeze or chill; it is not aptto leak when in use and is more eiiicient than the conventional tubularcooling unit, due to the fact that it has relatively few joints and isprovided with large unobstructedv passageways through which therefrigerating medium can circulate freely. The unit is of goodmechanical appearance and it can be provided with an attractive finish,on account of the fact that it is constructed from material that has asmooth surface. Moreover, it is compact; it is exceptionally ei.

, claim as new and desire to secure by Letters Patent is:

1. A cooling unit tems, composed of two shells arranged one within theother in spaced relation and provided with co-acting portions which formhollow side walls that contain a refrigerating medium and which surrounda center s ace in which articles or materials may be p aced, the hollowwall at the top of said for refrigerating sysspace serving as a floatchamber, the hollow Wall at the bottom of said space serving as a coldplate for abstracting heat rapidly from a fiat bottom receptaclepositioned in said space, and the hollow Walls at the sides of saidspace serving as circulating passage- Ways which connect the cold platewith the float chamber.

2. A cooling unit for refrigerating systems, composed of an outer shellhaving a top, a bottom and side Walls joined together, an inner shellprovided With corresponding Walls arranged inside of the outer shell inspaced relation with same so as to form a space for receiving materialsor articles, and a refrigerating medium in the space between saidshells, the top Walls of said shells being spaced far enough apart toform a oat chamber and the rear end portions of said top Walls beingbent towards each other and connected together by a gas-tight joint, theco-acting side Wall and bottom wall portions of said shells consistingof fiat p1ate-1ike members connected vtogether at intervals by spotWelds. I

- EDWIN H. STEEDMAN.

